I use Carbon Copy Cloner for both Mac OS and image back up and it works fine. Super Duper's UI is a bit friendlier perhaps, but functionally there's not much difference -- either can schedule copies at the file, folder or partition level -- with or without overwriting and deletion -- and both can create a bootable copy of the Mac OS. I use CCC to schedule daily and weekly copies of my OS to separate bootable partitions, so it's really easy to fix or re-install a bad OS on the fly without any downtime other than a system restart. I only keep Time Machine running so I have historical access to my document and email files, though could certainly do a system rebuild from it if the need ever arises.
